JAVA http请求接口数据

本次以访问百度地图服务API 为例 

 编写访问程序 

一、解析url 方法  把返回数据 封装成StringBuffer 字符串

public static StringBuffer httpsRequest(String requestUrl, String requestMethod, String output) throws IOException,

        UnsupportedEncodingException {

    URL url = new URL(requestUrl);

    if (requestUrl.startsWith("https")) {

        HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();

        connection.setDoOutput(true);

        connection.setDoInput(true);

        connection.setUseCaches(false);

        connection.setRequestMethod(requestMethod);

        if (null != output) {

            OutputStream outputStream = connection.getOutputStream();

            outputStream.write(output.getBytes("UTF-8"));

            outputStream.close();

        }

        // 从输入流读取返回内容

        InputStream inputStream = connection.getInputStream();

        InputStreamReader inputStreamReader = new InputStreamReader(inputStream, "utf-8");

        BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

        String str = null;

        StringBuffer buffer = new StringBuffer();

        while ((str = bufferedReader.readLine()) != null) {

            buffer.append(str.trim());

        }

        bufferedReader.close();

        inputStreamReader.close();

        inputStream.close();

        inputStream = null;

        connection.disconnect();

        return buffer;

    } else {

        HttpURLConnection connection = (HttpURLConnection) url.openConnection();

        connection.setDoOutput(true);

        connection.setDoInput(true);

        connection.setUseCaches(false);

        connection.setRequestMethod(requestMethod);

        if (null != output) {

            OutputStream outputStream = connection.getOutputStream();

            outputStream.write(output.getBytes("UTF-8"));

            outputStream.close();

        }

        // 从输入流读取返回内容

        InputStream inputStream = connection.getInputStream();

        InputStreamReader inputStreamReader = new InputStreamReader(inputStream, "utf-8");

        BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

        String str = null;

        StringBuffer buffer = new StringBuffer();

        while ((str = bufferedReader.readLine()) != null) {

            buffer.append(str.trim());

        }

        bufferedReader.close();

        inputStreamReader.close();

        inputStream.close();

        inputStream = null;

        connection.disconnect();

        return buffer;

    }

}

二、调用解析方法 处理接口返回数据

/**
 * 地铁信息类
 * @return
 */
public class StationInfo {

    private String stationName;

    private String lng;

    private String lat;

    private String subway;

    public String getStationName() {

        return stationName;

    }

    public void setStationName(String stationName) {

        this.stationName = stationName;

    }

    public String getLng() {

        return lng;

    }

    public void setLng(String lng) {

        this.lng = lng;

    }

    public String getLat() {

        return lat;

    }

    public void setLat(String lat) {

        this.lat = lat;

    }

    public String getSubway() {

        return subway;

    }

    public void setSubway(String subway) {

        this.subway = subway;

    } 

}

/**

 * 根据经纬度，及其范围距离来获取地铁站点集合

 * @param lng

 * @param lat

 * @param range

 * @return

 */

public List<StationInfo> getStationByLngLat(String lng, String lat, int range){

    int radius=range;//搜索的半径范围  

    String url="http://api.map.baidu.com/place/v2/search?query=地铁站&page_size=10&page_num=0&scope=1&location="+lat+","+lng+"&radius="+radius+"&output=json&ak={百度服务API秘钥}";

    List<StationInfo> list=new ArrayList<StationInfo>();

    try {

        //  System.out.println(HttpConnectionUtil.httpsRequest(url, "GET", null).toString());

        JSONObject jsonObject= JSONObject.fromObject( HttpConnectionUtil.httpsRequest(url, "GET", null).toString());

       // System.out.println("我是："+jsonObject.get("results"));

        // System.out.println("我是2："+jsonObject.get("total"));

        JSONArray arrays=jsonObject.getJSONArray("results");

        if(arrays==null){//如果没有则返回空

            return null;

        }

        if(arrays.size()>0){

            for (int i=0;i<arrays.size();i++){

                StationInfo stationInfo=new StationInfo();

                JSONObject jsonObject1=JSONObject.fromObject(arrays.getJSONObject(i));

                stationInfo.setLat(jsonObject1.getJSONObject("location").get("lat").toString());

                stationInfo.setLat(jsonObject1.getJSONObject("location").get("lng").toString());

                stationInfo.setStationName(jsonObject1.get("name").toString());

                String subwayStr=jsonObject1.get("address").toString();

                String[] subways=subwayStr.split(";");

                stationInfo.setSubway(subways[0]);

                list.add(stationInfo); 

            }

        }

    } catch (IOException e) {

        e.printStackTrace();

    }

    return list;

}

      

/**

 * 调用方法查看结果

 */

public static void main(String[] args) throws Exception {

    String lat = "39.915"; 

    String lng = "116.404";  

    Integer radius = 500; // 圆形区域大小

    MapUtil mapUtil = new MapUtil();

    List<StationInfo> list = mapUtil.getStationByLngLat(lng, lat, radius);

    for (StationInfo temp : list) {

        System.out.println(temp.getStationName());

    }

}